Tcpdump is a command-line packet analysis tool. We can use tcpdump to capture ssh traffic to troubleshoot connection issues and look for potential security issues on a network. What is SSH? SSH, which stands for Secure Shell, is a…
Analyzing disk issues is an important task for Linux admins. Disk I/O bottlenecks can bring down applications. In this tutorial, we will learn how to check disk space usage, disk load usage, disk iops, disk latency. Hope this post can…
Tcpdump is a very powerful Linux command to capture DNS packets. DNS is short for Domain Name System. It is a database that links meaningful names to a specific IP address. We can use tcpdump to filter DNS packets to…
ICMP is a network layer protocol used by network devices to diagnose network communication issues. Tcpdump command on Linux can be used to capture network packets. We can use the following examples to capture ICMP and ICMPv6 packets with tcpdump…
Nethogs is a Linux command that allows us to view network usage of a running process in realtime. Nethogs sorts the output by process and network bandwidth usage. We can quickly find out which process is using more bandwidth. This…
This article is part of the following series. Iotop is an interactive real-time I/O usage monitoring tool to check disk read and write bandwidth usage for each running process on Linux. Iotop is very useful to troubleshoot disk performance…
Timeo is a timeout mount option in NFS mount. It is the timeout value that the NFS client uses to wait for a response before it retries an NFS request. Let’s dive into the details about what this timeout value…
If you’re a Linux system administrator, then you’re probably familiar with DNS, which is a critical component of networking. TCPdump is a powerful Linux command that can help you capture and filter network packets. With TCPdump, you can analyze DNS…
Top is a very powerful command to periodically display a sorted list of system processes. The default sorting key is %CPU on Linux. Below we collect 3 ways to sort processes by memory. Understanding top command in Linux The top…
Tcpdump command in Linux can be used to capture ICMP packets. We will start with ICMP protocol introduction and then check out how to filter ICMP and ICMPv6 packets with tcpdump command. What is ICMP? ICMP is short for Internet…
